@blazm. Before I erased the partition table, I did find bad blocks too on my Reader and I had marked them as bad. I shouldn't have done that because that was blocking me from doing backups.
Luckily I had done a backup of the faulty reader, while it was faulty but before checking and marking bad blocks. Therefore I was able to erase the partition table (and therefore bad block markings), restore faulty backup and then restore partitions from good Reader.